Method and kit for detecting lead in a solid sample

Abstract

A method and kit for detecting the presence of lead in a solid sample is disclosed. The solid sample is brought into contact with a nonaqueous solution of a dithiocarbamate capable of forming a gel upon contact with lead, with the formation of a gel showing that lead is present in the solid sample.

The invention claimed is: 
     
       1. A method of determining a presence or absence of lead in a solid sample comprising:
 (a) providing a nonaqueous solution of a dithiocarbamate comprising a dibenzyldithiocarbamate, diallyldithiocarbamate, allylbenzyldithiocarbamate, 
 
       
         
           
           
               
               
           
         
       
       or mixtures thereof;
 (b) providing a test amount of a solid sample of interest; 
 (c) contacting the nonaqueous solution of (a) with the solid sample test amount of (b) and observing the resulting mixture for the formation of a gel, wherein the formation of a gel indicates the presence of lead. 
 
     
     
       2. The method of  claim 1  performed at a temperature of 20° C. to 50° C. 
     
     
       3. The method of  claim 1  performed at a temperature of greater than 20° C. to 30° C. 
     
     
       4. The method of  claim 1  wherein the nonaqueous solvent further comprises up to 50%, by volume, water. 
     
     
       5. The method of  claim 1  wherein the solid sample contains 200 ppm or more of lead. 
     
     
       6. The method of  claim 1 , wherein the solid sample is a paint sample. 
     
     
       7. The method of  claim 1 , wherein the nonaqueous solvent comprises an alcohol, an ester, a glycol, a glycol ether, an aliphatic hydrocarbon, an aromatic hydrocarbon, a chlorinated solvent, and mixtures thereof. 
     
     
       8. The method of  claim 1 , wherein the nonaqueous solvent comprises a C 1-6 alcohols, a monoC 1-4 alkyl ether of ethylene glycol or propylene glycol, acetone, methyl ethyl ketone, isophorone, dichloromethane, chloroform, ethyl acetate, 2-methoxyethanol, DMF, DMSO, THF, acetonitrile, kerosene, mineral spirits, xylene, toluene, turpentine, paint thinner, and mixtures thereof. 
     
     
       9. The method of  claim 1 , wherein the nonaqueous solvent further comprises up to 50%, by volume, water. 
     
     
       10. The method of  claim 1 , wherein the dithiocarbonate comprises sodium dibenzyldithiocarbonate.